My goals for this project are to develop and use biostatistical, biomathematical and epidemiologic methods aimed at reducing cancer occurrence. The objectives of my research are twofold. First, I will develop new methods for the conduct of epidemiologic studies of cancer etiology in relation to personal characteristics, lifestyle elements and environmental exposures. Specifically, I will develop better ways to design and analyze studies with exposure errors, better ways to analyze combined data from multicenter studies, and better ways to search out unusual patterns in population-based cancer incidence data. Second, I will use these methods to collect and analyze data relating site-specific cancer occurrence to modifiable lifestyle elements and environmental exposures. Existing data for analyses include data from a prospective study of site-specific cancers in college men and women, data from case-control studies of cancers of the ovary, breast, and large bowel, and data from the Surveillance, Epidemiology and End Results (SEER) and California tumor registries. New data will be generated from a recently funded five-year study of nonHodgkin's lymphoma, and from future multicenter studies of cancers of the prostate and ovary.